Internal combustion engines utilize a fuel mixing device such as a carburetor or a pressurized fuel injection system (hereinafter “carburetor”) in order to provide a combustible charge to the engine combustion chambers for ignition. Different intake assemblies have been used on the inlet side of the carburetor to provide a more efficient air flow and therefore increase the amount of charge delivered to the combustion chambers to increase the power output of the engine. One such apparatus is a velocity stack attached to the mouth of the carburetor. A velocity stack is a conical structure convergent in the direction of the carburetor inlet that directs the intake air flow and increases the density of the air mass as it enters the carburetor. Other structures providing the same function which do not have a circular cross-section have also been employed. It is further known to position the intake device so that it directly receives the air stream of the moving vehicle. This further increases engine horsepower by forcing a greater amount of air into the carburetor, and hence the engine, for yet greater power production. It is generally referred to as “ram air effect.” This ram air principle has been adopted on motorcycles, however it has not been utilized in an efficient and aesthetically acceptable way for the highly popular Harley Davidson® V-twin motorcycle engine because with this engine layout the carburetor is side-mounted.
U.S. Pat. No. 5,868,808 issued to Henderson discloses a carburetor air intake velocity stack engageable with a carburetor inlet. U.S. Pat. No. 6,780,214 issued to Leibold discloses an air intake scoop for a motorcycle carburetor. The Leibold air intake scoop has 90-degree air flow movement to take in air from the forward direction travel of the motorcycle and send it 90 degrees into the side-mounted mouth of the carburetor. U.S. Pat. No. 5,307,771 issued to Stahel II et al. discloses an intake assembly for delivering air to a motorcycle carburetor which includes a housing mountable on the carburetor that encloses an air filter. The Stahel housing includes forward-facing inlet ports which deliver air to the air filter, however any ram effect is negated by valve assemblies within the ports which prevent the overpressurization of the intake air.
What is needed is means for efficiently providing the ram air effect to a V-twin motorcycle engine carburetor that can increase engine horsepower output while providing an aesthetic appearance to the motorcycle.